PT  - JOURNAL ARTICLE
AU  - Smitha, K.A.
AU  - Arun, K.M.
AU  - Rajesh, P.G.
AU  - Thomas, B.
AU  - Kesavadas, C.
TI  - Resting-State Seed-Based Analysis: An Alternative to Task-Based Language fMRI and Its Laterality Index
AID  - 10.3174/ajnr.A5169
DP  - 2017 Jun 01
TA  - American Journal of Neuroradiology
PG  - 1187--1192
VI  - 38
IP  - 6
4099  - http://www.ajnr.org/content/38/6/1187.short
4100  - http://www.ajnr.org/content/38/6/1187.full
SO  - Am. J. Neuroradiol.2017 Jun 01; 38
AB  - BACKGROUND AND PURPOSE: Language is a cardinal function that makes human unique. Preservation of language function poses a great challenge for surgeons during resection. The aim of the study was to assess the efficacy of resting-state fMRI in the lateralization of language function in healthy subjects to permit its further testing in patients who are unable to perform task-based fMRI.MATERIALS AND METHODS: Eighteen healthy right-handed volunteers were prospectively evaluated with resting-state fMRI and task-based fMRI to assess language networks. The laterality indices of Broca and Wernicke areas were calculated by using task-based fMRI via a voxel-value approach. We adopted seed-based resting-state fMRI connectivity analysis together with parameters such as amplitude of low-frequency fluctuation and fractional amplitude of low-frequency fluctuation (fALFF). Resting-state fMRI connectivity maps for language networks were obtained from Broca and Wernicke areas in both hemispheres. We performed correlation analysis between the laterality index and the z scores of functional connectivity, amplitude of low-frequency fluctuation, and fALFF.RESULTS: Pearson correlation analysis between signals obtained from the z score of fALFF and the laterality index yielded a correlation coefficient of 0.849 (P < .05). Regression analysis of the fALFF with the laterality index yielded an R2 value of 0.721, indicating that 72.1% of the variance in the laterality index of task-based fMRI could be predicted from the fALFF of resting-state fMRI.CONCLUSIONS: The present study demonstrates that fALFF can be used as an alternative to task-based fMRI for assessing language laterality. There was a strong positive correlation between the fALFF of the Broca area of resting-state fMRI with the laterality index of task-based fMRI. Furthermore, we demonstrated the efficacy of fALFF for predicting the laterality of task-based fMRI.ALFFamplitude of low-frequency fluctuationBOLDblood oxygen level–dependentfALFFfractional amplitude of low-frequency fluctuationFCfunctional connectivityLIlaterality indexrsfMRIresting-state fMRI